This invention relates to expanded cans. In particular it relates to a can having a cylindrical side wall with a regular pattern of expanded elements. The cylindrical can side wall has either an integral base and a single can end (as in a so-called "two-piece" can) or is closed at both ends (as in a so-called "three-piece" or an aerosol can).
Cans having a patterned side wall have been produced in order to improve resistance against deformation by external pressure. These known cans have pattern elements which are pressed into the side wall of the can blank in order to provide improved axial load or panel performance. Since the elements are only provided for structural reasons, any "pattern" is often covered by a product label. In any case, these cans have only achieved limited shape definition, i.e. a shape which is clearly visible to a consumer, and reduce the capacity of the can of a particular aspect ratio.
EP-A-0 441 618 describes cans having patterned side walls which are typical of those referred to above. The pattern elements of EP-A-0 441 618 are formed entirely by pressing inwardly on the can side wall such that the pattern elements are externally concave with their sides being at the original side wall diameter.
U.S. Pat. No. 3,335,902 describes superimposed axial and circumferential beading rather than pattern elements.